2017 Mazda CX-9 Engine Problems

Owner reports

Selected complaints filed with NHTSA by 2017 Mazda CX-9 owners, lightly cleaned up (personal details are redacted by NHTSA).

The first sign of an issue was an oil pressure indicator on the dashboard, but upon inspection, the oil levels seemed completely normal. The dashboard light went away shortly after that. A day later, I was on my lunch break and parked my car in a garage for 45 minutes. On the drive there, I did not notice any issues and was able to operate the vehicle fine for the short distance that I drove. When I returned to my parked car, there was a large puddle of oil underneath. I immediately had a mechanic take a look at the car. The mechanic was able to identify a cracked cylinder head, which led to water and coolant entering the engine. He highly suspects that this caused a blown head gasket in the car as well. As well as that, the car's starter, which worked just fine on day 1 of the issue and has never had any problems before, has totally ceased function. …

Driving home the car said 26 miles to E. while in gear going down the road it popped engine system malfunction and the whole car shut off and wouldn't start. Didn't drive the vehicle for 2 days- filled the gas tank and it drove fine for 5 days. Day 6- 4/8/2023, fine driving down the highway 45 minutes. Go down about a mile and it still doesn't seem right, I move lanes and the thermostat light starts flashing at 260, as soon as I make the turn it tells me to pull over and turn the car off-it was at 270. Go to drive across the street to get coolant later- car stalls when I shift into drive. Park it- get coolant takes an entire jug. Idling a little rough, but not bad. Mechanic he can't see any issues, computer is throwing out fuel system codes but no, issues that can be found. Does a tune up on it, pick it up. Smoking when I start the car and something smells burning. …

My car gave me a warning that it was overheating... and gave me a warning to pull to the side of the road because of safety and turn off my car engine because the engine is overheating. I was on the highway when this occurred. The engine coolant light was well into the red zone. I had my two kids in the car and my service animal... The car was say overheating and blinking the engine coolant red warning sign I brought the vehicle to a dealership and it was confirmed that my engine coolant was leaking behind the gasket head and is damaging the turbo charger. The same issue word for word that was stated in the TSB... Yes the warning sign of engine overheating and the engine coolant light to high flashing showed up on the vehicle and the warning of pulling over to a safe place to allow the car to cool down. I was on the interstate when the problem occurred. …

My Mazda 2017 CX 9 apparently had a coolant leak. When we had our oil changed, we were told it looked like it was leaking from behind the turbo booster. As I was driving it yesterday, the car slowed to an almost complete stop on the interstate and a warning sign on the screen showed that it was overheating to a dangerous level. I immediately pulled over and allowed the car to cool down. I checked the coolant level and it was not very low at all, although I did add some coolant at that time. It continued to overheat and even blew tons of smoke out through the exhaust, so I had AAA tow to my home. After researching this, I have found that there was a bulletin posted in 2021 from Mazda about this very thing happening. My husband thinks that we may have a cracked block or a blown head gasket due to this overheating. …

Recently had my car into the local Madza dealer for oil change and break inspection. Soon after the oil change it started running rough. Then next thing I know it begins to overheat in the street at major intersection while driving home. Parked it let it cool down and then toed to Mazda dealer. Told antifreeze getting into the engine. I see Madza is aware of this issue and this engine is defective and can not handle turbo. I could have been killed at this very intersection so thankful I was safe. What if I was driving on the highway which I do every day this would have compromised many people's safety. This is a safety defect in that Mazda is knowing of this issue. The only warning was just as it happened. except it was riding a little rough at stops but no idea it was going to overheat. especially since it was just in the shop for the oil change. …

What component or system failed or malfunctioned, and is it available for inspection upon request? Cylinder head has cracked and the vehicle leaked coolant and overheated while driving leading to engine failure. Vehicle is available for inspection How was your safety or the safety of others put at risk? Car overheated while driving leading to engine failure Has the problem been reproduced or confirmed by a dealer or independent service center? Dealer has diagnosed the problem as a cracked cylinder head Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, dealer has diagnosed issue and recommended replacement Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Engine temperature sensor went off and within seconds car was not driveable due to fluid loss

This vehicle has been diagnosed as having the Cylinder Head Crack issue referenced in Mazda TSB 01-013/21. The car has just over 70,000 miles on it, so I understand it is out of Warranty, yet this issue only came up due to a known design flaw by Mazda. I have been told that I will be without the car for up to 9 weeks due to repair backlogs and the cost will be $5,250 plus tax!! This car has always been maintained at the Mazda dealership since purchase and has never had any other issues until this flaw, acknowledged by became an issue. Immediately, I brought it in, only to be told Mazda would not assist in a Good Faith repair. This is very sad that Mazda would do this to loyal customers, there should be a recall and this should not fall on customers pockets when we continue to give them business, trusting they would not knowingly put a full engine repair in their customers pockets

2017 Mazda CX-9 with crack in engine with coolant leaking out. Informed by mechanic that coolant was leaking out from the engine and was caught by heat shield. I smelled coolant, but never saw any on the ground. Per TSB 01-002/23 there is a crack that can develop in the engine due to stresses from the turbo/exhaust. A crack will develop near studs in the engine. Once crack develops, the coolant can leak out. However, in worst cases (which mine did not suffer from...yet), the coolant can leak into the engine and damage the internal components. Right now, I am looking at a $6254 repair bill to have a mechanic fix the engine. I will probably have to take this bill on as my family needs a second vehicle. Mazda needs to issue a recall that is the fault of their own, not the customer. This is occurring on too many vehicles, with turbos, from 2016-2020 CX-9s, CX-5s, and Mazda6s.

This problem has been documented and know by Mazda for awhile. They are aware that their 2.5 Turbo liter engine has the problem of cracking the cylinder head due to some overweight of the same engine component. My Mazda local dealer already inspected the car and told me that the fix is replacing the whole cylinder head, which with them would cost me 3.5k. My warranty company, which I purchased when buying this used car, didn't took responsibility of the repair cost because it was pre existing condition before I bought the car. Many people over the internet have reported this same issue happening to them, models year between 2016-2019. This issue cause a leaking of coolant. Which in my case has been a lot built up, to the point that you can grab it with your hands (the coolant residual).

Engine head cracked and is still on car as of now. If engine overheats, engine can seize. The leak has been reproduced, but the head has not been removed for inspection yet. No warning lamps. A large puddle of coolant was noticed under the vehicle. From what I have heard is that the material is too thin and eventually cracks. There is a tsb that covers the issue, but since we've gone beyond the 5 yrs of the powertrain warranty it won't be covered. We are under the mileage limit. We lucky caught the leak before engine damage took place (as far as we know, since the teardown has not been performed. If the replacement head is "reinforcing" that area then a design flaw has been inferred and should be corrected to avoid serious injuries due to a seized motor.

Engine complaints in other CX-9 years